mcs/class/corlib/System.Security/CodeAccessPermission.cs

   1 //
   2 // System.Security.CodeAccessPermission.cs
   3 //
   4 // Authors:
   5 //      Miguel de Icaza (miguel@ximian.com)
   6 //      Nick Drochak, ndrochak@gol.com
   7 //      Sebastien Pouliot  <sebastien@ximian.com>
   8 //
   9 // (C) Ximian, Inc. http://www.ximian.com
  10 // Copyright (C) 2001 Nick Drochak, All Rights Reserved
  11 // Portions (C) 2004 Motus Technologies Inc. (http://www.motus.com)
  12 // Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
  13 //
  14 // Permission is hereby granted, free of charge, to any person obtaining
  15 // a copy of this software and associated documentation files (the
  16 // "Software"), to deal in the Software without restriction, including
  17 // without limitation the rights to use, copy, modify, merge, publish,
  18 // distribute, sublicense, and/or sell copies of the Software, and to
  19 // permit persons to whom the Software is furnished to do so, subject to
  20 // the following conditions:
  21 //
  22 // The above copyright notice and this permission notice shall be
  23 // included in all copies or substantial portions of the Software.
  24 //
  25 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  26 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  27 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  28 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  29 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  30 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  31 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  32 //
  33
  34 using System.Diagnostics;
  35 using System.Globalization;
  36 using System.Reflection;
  37 using System.Runtime.CompilerServices;
  38 using System.Runtime.InteropServices;
  39 using System.Security.Permissions;
  40 using System.Threading;
  41
  42 namespace System.Security {
  43
  44         [Serializable]
  45         [SecurityPermission (SecurityAction.InheritanceDemand, ControlEvidence = true, ControlPolicy = true)]
  46         [ComVisible (true)]
  47         [MonoTODO ("CAS support is experimental (and unsupported).")]
  48         public abstract class CodeAccessPermission : IPermission, ISecurityEncodable, IStackWalk {
  49
  50
  51                 protected CodeAccessPermission ()
  52                 {
  53                 }
  54
  55 #if MOBILE
  56                 [Conditional ("MONO_FEATURE_CAS")]
  57 #else
  58                 [MonoTODO ("CAS support is experimental (and unsupported). Imperative mode is not implemented.")]
  59 #endif
  60                 public void Assert ()
  61                 {
  62                         new PermissionSet (this).Assert ();
  63                 }
  64
  65                 public abstract IPermission Copy ();
  66
  67 #if MOBILE
  68                 [Conditional ("MONO_FEATURE_CAS")]
  69 #endif
  70                 public void Demand ()
  71                 {
  72                         // note: here we're sure it's a CAS demand
  73                         if (!SecurityManager.SecurityEnabled)
  74                                 return;
  75
  76                         // skip frames until we get the caller (of our caller)
  77                         new PermissionSet (this).CasOnlyDemand (3);
  78                 }
  79
  80 #if MOBILE
  81                 [Conditional ("MONO_FEATURE_CAS")]
  82 #else
  83                 [MonoTODO ("CAS support is experimental (and unsupported). Imperative mode is not implemented.")]
  84 #endif
  85                 public void Deny ()
  86                 {
  87                         new PermissionSet (this).Deny ();
  88                 }
  89
  90                 [ComVisible (false)]
  91                 public override bool Equals (object obj)
  92                 {
  93                         if (obj == null)
  94                                 return false;
  95                         if (obj.GetType () != this.GetType ())
  96                                 return false;
  97                         CodeAccessPermission cap = (obj as CodeAccessPermission);
  98                         return (IsSubsetOf (cap) && cap.IsSubsetOf (this));
  99                 }
 100
 101                 public abstract void FromXml (SecurityElement elem);
 102
 103                 [ComVisible (false)]
 104                 public override int GetHashCode ()
 105                 {
 106                         return base.GetHashCode ();
 107                 }
 108
 109                 public abstract IPermission Intersect (IPermission target);
 110
 111                 public abstract bool IsSubsetOf (IPermission target);
 112
 113                 public override string ToString ()
 114                 {
 115                         SecurityElement elem = ToXml ();
 116                         return elem.ToString ();
 117                 }
 118
 119                 public abstract SecurityElement ToXml ();
 120
 121                 public virtual IPermission Union (IPermission other)
 122                 {
 123                         if (null != other)
 124                                 throw new System.NotSupportedException (); // other is not null.
 125                         return null;
 126                 }
 127
 128 #if MOBILE
 129                 [Conditional ("MONO_FEATURE_CAS")]
 130 #else
 131                 [MonoTODO ("CAS support is experimental (and unsupported). Imperative mode is not implemented.")]
 132 #endif
 133                 public void PermitOnly ()
 134                 {
 135                         new PermissionSet (this).PermitOnly ();
 136                 }
 137
 138 #if MOBILE
 139                 [Conditional ("MONO_FEATURE_CAS")]
 140 #else
 141                 [MonoTODO ("CAS support is experimental (and unsupported). Imperative mode is not implemented.")]
 142 #endif
 143                 public static void RevertAll ()
 144                 {
 145                         if (!SecurityManager.SecurityEnabled)
 146                                 return;
 147                         throw new NotImplementedException ();
 148                 }
 149
 150 #if MOBILE
 151                 [Conditional ("MONO_FEATURE_CAS")]
 152 #else
 153                 [MonoTODO ("CAS support is experimental (and unsupported). Imperative mode is not implemented.")]
 154 #endif
 155                 public static void RevertAssert ()
 156                 {
 157                         if (!SecurityManager.SecurityEnabled)
 158                                 return;
 159                         throw new NotImplementedException ();
 160                 }
 161
 162 #if MOBILE
 163                 [Conditional ("MONO_FEATURE_CAS")]
 164 #else
 165                 [MonoTODO ("CAS support is experimental (and unsupported). Imperative mode is not implemented.")]
 166 #endif
 167                 public static void RevertDeny ()
 168                 {
 169                         if (!SecurityManager.SecurityEnabled)
 170                                 return;
 171                         throw new NotImplementedException ();
 172                 }
 173
 174 #if MOBILE
 175                 [Conditional ("MONO_FEATURE_CAS")]
 176 #else
 177                 [MonoTODO ("CAS support is experimental (and unsupported). Imperative mode is not implemented.")]
 178 #endif
 179                 public static void RevertPermitOnly ()
 180                 {
 181                         if (!SecurityManager.SecurityEnabled)
 182                                 return;
 183                         throw new NotImplementedException ();
 184                 }
 185
 186                 // Internal helpers methods
 187
 188                 // snippet moved from FileIOPermission (nickd) to be reused in all derived classes
 189                 internal SecurityElement Element (int version)
 190                 {
 191                         SecurityElement se = new SecurityElement ("IPermission");
 192                         Type type = this.GetType ();
 193                         se.AddAttribute ("class", type.FullName + ", " + type.Assembly.ToString ().Replace ('\"', '\''));
 194                         se.AddAttribute ("version", version.ToString ());
 195                         return se;
 196                 }
 197
 198                 internal static PermissionState CheckPermissionState (PermissionState state, bool allowUnrestricted)
 199                 {
 200                         string msg;
 201                         switch (state) {
 202                         case PermissionState.None:
 203                                 break;
 204                         case PermissionState.Unrestricted:
 205                                 // unrestricted permissions are possible for identiy permissions
 206                                 break;
 207                         default:
 208                                 msg = String.Format (Locale.GetText ("Invalid enum {0}"), state);
 209                                 throw new ArgumentException (msg, "state");
 210                         }
 211                         return state;
 212                 }
 213
 214                 internal static int CheckSecurityElement (SecurityElement se, string parameterName, int minimumVersion, int maximumVersion)
 215                 {
 216                         if (se == null)
 217                                 throw new ArgumentNullException (parameterName);
 218
 219                         // Tag is case-sensitive
 220                         if (se.Tag != "IPermission") {
 221                                 string msg = String.Format (Locale.GetText ("Invalid tag {0}"), se.Tag);
 222                                 throw new ArgumentException (msg, parameterName);
 223                         }
 224
 225                         // Note: we do not care about the class attribute at
 226                         // this stage (in fact we don't even if the class
 227                         // attribute is present or not). Anyway the object has
 228                         // already be created, with success, if we're loading it
 229
 230                         // we assume minimum version if no version number is supplied
 231                         int version = minimumVersion;
 232                         string v = se.Attribute ("version");
 233                         if (v != null) {
 234                                 try {
 235                                         version = Int32.Parse (v);
 236                                 }
 237                                 catch (Exception e) {
 238                                         string msg = Locale.GetText ("Couldn't parse version from '{0}'.");
 239                                         msg = String.Format (msg, v);
 240                                         throw new ArgumentException (msg, parameterName, e);
 241                                 }
 242                         }
 243
 244                         if ((version < minimumVersion) || (version > maximumVersion)) {
 245                                 string msg = Locale.GetText ("Unknown version '{0}', expected versions between ['{1}','{2}'].");
 246                                 msg = String.Format (msg, version, minimumVersion, maximumVersion);
 247                                 throw new ArgumentException (msg, parameterName);
 248                         }
 249                         return version;
 250                 }
 251
 252                 // must be called after CheckSecurityElement (i.e. se != null)
 253                 internal static bool IsUnrestricted (SecurityElement se)
 254                 {
 255                         string value = se.Attribute ("Unrestricted");
 256                         if (value == null)
 257                                 return false;
 258                         return (String.Compare (value, Boolean.TrueString, true, CultureInfo.InvariantCulture) == 0);
 259                 }
 260
 261                 internal static void ThrowInvalidPermission (IPermission target, Type expected)
 262                 {
 263                         string msg = Locale.GetText ("Invalid permission type '{0}', expected type '{1}'.");
 264                         msg = String.Format (msg, target.GetType (), expected);
 265                         throw new ArgumentException (msg, "target");
 266                 }
 267
 268 #if MOBILE
 269                 // Workaround for CS0629
 270                 void IStackWalk.Assert ()
 271                 {
 272                 }
 273
 274                 void IStackWalk.Deny ()
 275                 {
 276                 }
 277
 278                 void IStackWalk.PermitOnly ()
 279                 {
 280                 }
 281
 282                 void IStackWalk.Demand ()
 283                 {
 284                 }
 285
 286                 void IPermission.Demand ()
 287                 {
 288                 }
 289 #endif
 290         }
 291 }